rTMS and Botulinum Toxin in Benign Essential Blepharospasm
Benign Essential Blepharospasm
About this trial
This is an interventional treatment trial for Benign Essential Blepharospasm
Eligibility Criteria
Inclusion Criteria:
- subjects diagnosed with blepharospasm or cranio-cervical dystonia who receive BoNT therapy at the Center for Movement Disorders will be approached. The investigators will enroll only those subjects who report experiencing positive benefits with BoNT but lasting about 10 weeks or less.
Exclusion Criteria:
- pregnancy
- active seizure disorder
- significant cognitive impairment
- exposure to neuroleptics
- presence of a metallic body such as pacemaker, implants, prosthesis, artificial limb or joint, shunt, metal rods and hearing aid.
Sites / Locations
- Center for Movement Disorders and Neurorestoration
Arms of the Study
Arm 1
Arm 2
Experimental
Sham Comparator
Real rTMS stimulation
Sham rTMS Stimulation
Repetitious transcranial magnetic stimulation (rTMS) will be delivered using the Magstim RapidStim2 over each anterior cingulate cortex, using a figure-of-eight coil. The investigators will apply rTMS with 0.2 Hz frequency to the ACC. 180 stimuli will be delivered with a stimulator output of 100% active motor threshold (AMT). AMT will be assessed at the tibialis anterior muscle with the coil. The AMT will be defined as the lowest stimulation intensity required to evoke a 150 μV potential in the target muscle. To determine the stimulation site for ACC, the coil will be placed over Fz and then moved over the midline of the brain in 0.5-cm steps anteriorly, until the point of maximum motor evoked potential in the orbicularis oculi (OO) muscle. The coil position will be marked on the skin. These rTMS sessions will be repeated daily for 10 days.
During sham repetitious transcranial magnetic stimulation (rTMS), subjects will undergo the same procedure for identifying stimulus location as used in patients receiving real rTMS using the sham Magstim RapidStim2 coil. This coil will be placed on the patient's head in an identical manner however will not be connected to the Magstim device. Instead another coil will be connected to provide stimulation sound. In each stimulation condition, the Magstim will be placed behind the patient and not visible to him or her. Placebo sham coil which produces discharge noise and vibration similar to a real coil without stimulating the cerebral cortex. During rTMS, all patients will continue to wear ear plugs as instructed during the real stimulation sessions.